re: Room for amatuers- I agree but let me add
> wonder if the sciences will ever get to the point that there is not enough time in a human lifetime to truly understand them....
I think we're there now - it's called specialization ..
but no-one should be discouraged from mastering a discipline if that's where they want to go. The sciences might be too complicated to master in all their nooks and crannies but you can still attain a very comprehensive and deep understanding of the topic(s) regardless.
I mean for gossakes even (for example) 2 astrophysicists from different areas will often have little to discuss with each other. 'Professionalism' is not always all it's cracked up to be, I would say ..